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2.
In this paper we consider an initial boundary value problem for a reaction-diffusion equation under nonlinear and nonlocal Robin type boundary condition. Assuming the existence of an ordered pair of upper and lower solutions we establish a generalized quasilinearization method for the problem under consideration whose characteristic feature consists in the construction of monotone sequences converging to the unique solution within the interval of upper and lower solutions, and whose convergence rate is quadratic. Thus this method provides an efficient iteration technique that produces not only improved approximations due to the monotonicity of its iterates, but yields also a measure of the convergence rate. 相似文献
3.
D. I. Naiduss W. W. Kiesewetter S. L. Dikanskaja J. Schapiro R. Meurice J. Cartiaux E. F. Posorski G. N. Murthy S. Mihaéloff A. D. Rich J. J. Vollertsen Gh. Ghimicescu G. Kotsis C. T. Townsend J. A. Esty F. C. Baselt R. Dubrisay J. Gascon E. R. Scheggia K. M. Renner E. S. Miller C. A. Mitchell A. G. Sossin und S. E. Spektor 《Fresenius' Journal of Analytical Chemistry》1939,118(1-2):48-51
Ohne Zusammenfassung 相似文献
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Ohne ZusammenfassungDie folgende Untersuchung trug der leider so früh dem Dienste der Wissenschaft durch den Tod entrissene Privatdocent Dr. Hierholzer dahier (gest. 13. Sept. 1871) einem Kreise befreundeter Mathematiker vor. Um sie vor Vergessenheit zu bewahren, musste sie bei dem Mangel jeder schriftlichen Aufzeichnung aus dem Gedächtniss wieder hergestellt werden, was ich unter Beihilfe meines verehrten Collegen Lüroth durch das Folgende möglichst getreu auszuführen suchte. 相似文献
6.
S. Carl 《Journal of Differential Equations》2004,199(1):77-95
In this paper we consider systems of quasilinear elliptic variational inequalities, and prove the existence of minimal and maximal (in the set theoretical sense) solutions within some ordered interval of an appropriately defined pair of sub- and supersolutions. We show that the notion of sub- and supersolutions of variational inequalities introduced here is consistent with the usual notion of sub-supersolutions for (variational) equations. For weakly coupled quasimonotone systems of variational inequalities the existence of smallest and greatest solutions is proved. 相似文献
7.
Eitan Altman Konstantin Avrachenkov Richard Marquez Gregory Miller 《Mathematical Methods of Operations Research》2005,62(3):375-386
We consider a zero-sum stochastic game with side constraints for both players with a special structure. There are two independent
controlled Markov chains, one for each player. The transition probabilities of the chain associated with a player as well
as the related side constraints depend only on the actions of the corresponding player; the side constraints also depend on
the player’s controlled chain. The global cost that player 1 wishes to minimize and that player 2 wishes to maximize, depend
however on the actions and Markov chains of both players. We obtain a linear programming formulations that allows to compute
the value and saddle point policies for this problem. We illustrate the theoretical results through a zero-sum stochastic
game in wireless networks in which each player has power constraints 相似文献
8.
Compared with linear polymers, more factors may affect the glass‐transition temperature (Tg) of a hyperbranched structure, for instance, the contents of end groups, the chemical properties of end groups, branching junctions, and the compactness of a hyperbranched structure. Tg's decrease with increasing content of end‐group free volumes, whereas they increase with increasing polarity of end groups, junction density, or compactness of a hyperbranched structure. However, end‐group free volumes are often a prevailing factor according to the literature. In this work, chain‐end, free‐volume theory was extended for predicting the relations of Tg to conversion (X) and molecular weight (M) in hyperbranched polymers obtained through one‐pot approaches of either polycondensation or self‐condensing vinyl polymerization. The theoretical relations of polymerization degrees to monomer conversions in developing processes of hyperbranched structures reported in the literature were applied in the extended model, and some interesting results were obtained. Tg's of hyperbranched polymers showed a nonlinear relation to reciprocal molecular weight, which differed from the linear relation observed in linear polymers. Tg values decreased with increasing molecular weight in the low‐molecular‐weight range; however, they increased with increasing molecular weight in the high‐molecular‐weight range. Tg values decreased with increasing log M and then turned to a constant value in the high‐molecular‐weight range. The plot of Tg versus 1/M or log M for hyperbranched polymers may exhibit intersecting straight‐line behaviors. The intersection or transition does not result from entanglements that account for such intersections in linear polymers but from a nonlinear feature in hyperbranched polymers according to chain‐end, free‐volume theory. However, the conclusions obtained in this work cannot be extended to dendrimers because after the third generation, the end‐group extents of a dendrimer decrease with molecular weight. Thus, it is very possible for a dendrimer that Tg increases with 1/M before the third generation; however, it decreases with 1/M after the third generation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1235–1242, 2004 相似文献
9.
V.B. Fainerman V.N. Kazakov S.V. Lylyk A.V. Makievski R. Miller 《Colloids and surfaces. A, Physicochemical and engineering aspects》2004,250(1-3):97-102
One of the essential differences in the design of bubble pressure tensiometers consists in the geometry of the measuring capillaries. To reach extremely short adsorption times of milliseconds and below, the so-called deadtime of the capillaries must be of the order of some 10 ms. In particular, for concentrated surfactant solutions, such as micellar solutions, short deadtimes are needed to minimize the initial surfactant load of the generated bubbles. A theoretical model is derived and confirmed by experiments performed for a wide range of experimental conditions, mainly in respect to variations in deadtime and bubble volume. 相似文献
10.
Arne Miller 《Radiation Physics and Chemistry》1993,42(4-6):581-584
The activities and services of the accredited Risø High Dose Reference Laboratory are described. The laboratory operates according to the European standard EN 45001 regarding Operation of Testing Laboratories, and it fulfills the requirements of being able to deliver traceable dose measurements for control of radiation sterilization. The accredited services include:
1. 1. Irradiation of dosimeters and test samples with cobalt-60 gamma rays.
2. 2. Irradiation of dosimeters and test samples with 10 MeV electrons.
3. 3. Issue of and measurement with calibrated dosimeters.
4. 4. Measurement of the dosimetric parameters of an irradiation facility.
5. 5. Measurement of absorbed dose distribution in irradiated products.
The paper describes these services and the procedures necessary for their execution. 相似文献